1. Field of the Invention
The present invention generally relates to electrical stimulation of muscles, and more particularly, relates to electrical stimulation of muscles for the treatment of a medical condition.
2. Description of the Prior Art
It has been known to electrically stimulate muscular contractions since the beginnings of experimentation with electricity. In more recent times, electrical stimulation of muscle tissue has been used therapeutically. The effects of chronic stimulation have been studied by Ciske and Faulkner in "Chronic Electrical Stimulation of Nongrafted and Grafted Skeletal Muscles in Rats", in Journal of Applied Physiology, Volume 59(5), pp. 1434-1439 (1985). Bernotas et al., have even suggested the rudiments of adaptive control in "Adaptive Control of Electrically Stimulated Muscle", in IEEE Transactions on Biomedical Engineering, Volume BME-34, No. 2, pp. 140-147, (February 1987).
A review of early attempts at electrical stimulation associated with the respiratory system is found in "Diaphragm Pacing: Present Status", by William W. L. Glenn, in Pace, Volume pp. 357-370, (July-September 1978). Much work has been done in electrical stimulation within the cardiovascular system by way of cardiac pacing.
Treatment of obstructive sleep apnea using electrical stimulation has also been discussed. "Laryngeal Pacemaker, II Electronic Pacing of Reinnervated Posterior Cricoarytenoid Muscles in the Canine", by Broniatowski et al, in Laryngoscope, Volume 95, pp. 1194-1198 (October 1985); "Assessment of Muscle Action on Upper Airway Stability in Anesthetized Dogs", by Strohl et al., in Journal of Laboratory Clinical Medicine, Volume 110, pp. 221-301, (1987); U.S. Pat. No. 4,830,008 issued to Meer; and U.S. Pat. No. 4,570,631 issued to Durkan all discuss electrical stimulation of the upper airway to treat obstructive sleep apnea.